Analyzing 9,108,2729.1M ReviewsFor 25,80125.8K Experts
We graded 10 companies on seven things customers actually report: satisfaction, reliability, workmanship, value, momentum, track record and how owners handle complaints.
From 4,880 Google reviews of 18 top-rated insulation contractors nationwide; 10 of them in Grandville, MI. Updated November 9, 2026.
Pick the job — we re-rank companies by how customers rated that exact job.
Experts Score 0–100Experts Score (0–100)Absolute quality first: recency-weighted star average (≈54%), share of 1–2★ reviews (≈24%), customers’ price verdicts (≈14%), owner replies to critical reviews (≈7%); minus up to 10 points each for complaints flagged in Google review highlights and for a real slide in recent ratings. Hover a company’s score on its page for the full breakdown. and a letter grade per factor (A = top 20% of insulation contractors).
| # | Company | ScoreExperts Score (0–100)Absolute quality first: recency-weighted star average (≈54%), share of 1–2★ reviews (≈24%), customers’ price verdicts (≈14%), owner replies to critical reviews (≈7%); minus up to 10 points each for complaints flagged in Google review highlights and for a real slide in recent ratings. Hover a company’s score on its page for the full breakdown. | FactorsFactor grades, in orderSatisfaction (54%): Recency-weighted star average (2-year half-life), shrunk toward the category mean by review volume; the company’s own lifetime average as the prior; absolute: 4.0★ = 0, 5★ = 100.Reliability (24%): How rarely jobs go badly: share of 1–2★ reviews — 60% the last 24 months (or the 20 newest if fewer), 40% all-time; 0% = 100, 15%+ = 0; the category percentile can only raise it.Craft & service (0%): Google review highlights: Quality, Professionalism, Responsiveness, Punctuality — how rarely reviewers flag them as a negative, per review since highlights began; 0% = 100, 5%+ = 0. Subtracted from the score (up to −10), never averaged in — clean highlights are the norm, not a bonus.Value (14%): Customers’ own price verdicts (Great / Reasonable vs Overpriced) and Value highlights; 65% absolute (all “reasonable” ≈ 80, “great” = 100), the category percentile can only raise it.Momentum (0%): Penalises only a real slide: last-12-month average below lifetime (−0.5★ = 0). Still 4.8★+ over the last year, or steady/improving = 100. Subtracted from the score (up to −10), never averaged in.Replies to reviews (7%): How often the owner publicly replies to reviews under 5★ (1–4★). Needs 3+ such reviews, otherwise not counted; 65% absolute (80%+ replied = 100), the category percentile can only raise it.One letter per factor score: A = 80+, B = 60–79, C = 40–59, D = 20–39, F = below 20. | ★Google star rating as shown on Google Maps. | Typical billMedian bill customers of this company reported in their reviews (needs 3+ priced reviews). |
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| 1 |  Michigan Spray Foam InsulationGrandville, MI | A 95How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 69%94+65.1Reliability 31%96+29.5Experts Score= 95Not enough data for value, replies to reviews; its weight is shared by the others.Grade A: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | AA–––– | 4.93 | — |
| 2 |  Grandville Roofing and SidingGrandville, MI | A 94How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 59%93+54.6Reliability 26%95+24.8Value 15%100+15.2Craft & service penalty97−0.3Experts Score= 94Not enough data for replies to reviews; its weight is shared by the others.Grade A: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | AAAAA– | 4.95 | $17k |
| 3 |  Melvin Belk RoofingGrandville, MI | A 92How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 55%91+49.6Reliability 24%88+21.3Value 14%100+14.1Replies to reviews 7%100+7.1Experts Score= 92Grade A: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | AAAAAA | 4.89 | $7.1k |
| 4 |  Gutter Helmet Of Michigan and IllinoisGrandville, MI | A 92How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 55%96+52.4Reliability 24%91+22.1Value 14%100+14.1Replies to reviews 7%45+3.2Experts Score= 92Grade A: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | AA–AAC | 4.90 | — |
| 5 |  Premier Roofing & ExteriorsGrandville, MI | A 89How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 55%92+50.2Reliability 24%87+21.1Value 14%100+14.1Replies to reviews 7%61+4.3Craft & service penalty95−0.5Experts Score= 89Grade A: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | AAAAAB | 4.91 | $16k |
| 6 |  The Roof Dr.Grandville, MI | A 85How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 55%90+49.1Reliability 24%82+19.9Value 14%100+14.1Replies to reviews 7%54+3.8Craft & service penalty79−2.1Experts Score= 85Grade A: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | AABAAC | 4.89 | $4.1k |
| 7 |  Michigan Spray Foam InsulationGrandville, MI | A 85How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 69%84+58.2Reliability 31%88+27.1Experts Score= 85Not enough data for value, replies to reviews; its weight is shared by the others.Grade A: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | AA––A– | 4.80 | — |
| 8 |  WMGB Home Improvement (Formerly West Michigan Glass Block)Grandville, MI | B 78How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 55%81+44.2Reliability 24%72+17.5Value 14%100+14.1Replies to reviews 7%100+7.1Craft & service penalty86−1.4Momentum penalty62−3.8Experts Score= 78Grade B: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | ABAABA | 4.85 | — |
| 9 |  Koala Insulation of Grand RapidsGrandville, MI | B 78How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 55%82+44.7Reliability 24%73+17.7Value 14%99+14Replies to reviews 7%100+7.1Momentum penalty43−5.7Experts Score= 78Grade B: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | ABAACA | 4.85 | — |
| 10 |  Georgetown Waterproofing IncGrandville, MI | B 60How the Experts Score is calculatedEach factor is scored 0–100 on absolute terms (standing in the category can only raise it), then weighted; problems flagged in review highlights or a recent slide in ratings are subtracted:Satisfaction 59%68+39.9Reliability 26%57+14.9Value 15%93+14.2Craft & service penalty98−0.2Momentum penalty15−8.5Experts Score= 60Not enough data for replies to reviews; its weight is shared by the others.Grade B: A = 80+, B = 60–79, C = 40–59, D = 20–39. Needs 10+ reviews. | BCAAF– | 4.77 | — |
What customers paid, from the price Google asks reviewers to report.
| Job | Low25th percentile: 1 in 4 customers paid less than this. | TypicalMedian of the bill customers reported in their Google review (Google asks reviewers for a price range; we use the middle of each range). | High75th percentile: 1 in 4 customers paid more than this. | FairOf customers who rated the price, the share who chose “Great price” or “Reasonable” rather than “Overpriced”. |
|---|---|---|---|---|
| Roof installation | $13k | $17k | $20k | 99% |
| Roof repair | $927 | $4.1k | $13k | 100% |
| Roof repair for storm & wind damage | $1.1k | $12k | $20k | 100% |
How the 10 insulation contractors we rated in Grandville, MI compare, and what customers praise most.
A = score 80+, F = below 20.
Average stars per company.
Share of Google review highlights.
All price verdicts left with reviews.
Share calling it great / reasonable / overpriced.
Satisfaction (54%) — Recency-weighted star average (2-year half-life), shrunk toward the category mean by review volume; the company’s own lifetime average as the prior; absolute: 4.0★ = 0, 5★ = 100.
Reliability (24%) — How rarely jobs go badly: share of 1–2★ reviews — 60% the last 24 months (or the 20 newest if fewer), 40% all-time; 0% = 100, 15%+ = 0; the category percentile can only raise it.
Craft & service (penalty, up to −10) — Google review highlights: Quality, Professionalism, Responsiveness, Punctuality — how rarely reviewers flag them as a negative, per review since highlights began; 0% = 100, 5%+ = 0. Subtracted from the score (up to −10), never averaged in — clean highlights are the norm, not a bonus.
Value (14%) — Customers’ own price verdicts (Great / Reasonable vs Overpriced) and Value highlights; 65% absolute (all “reasonable” ≈ 80, “great” = 100), the category percentile can only raise it.
Momentum (penalty, up to −10) — Penalises only a real slide: last-12-month average below lifetime (−0.5★ = 0). Still 4.8★+ over the last year, or steady/improving = 100. Subtracted from the score (up to −10), never averaged in.
Replies to reviews (7%) — How often the owner publicly replies to reviews under 5★ (1–4★). Needs 3+ such reviews, otherwise not counted; 65% absolute (80%+ replied = 100), the category percentile can only raise it.
The 10 best-rated insulation contractors in Grandville, MI average 4.9★ on Google across 3,923 reviews. Grandville Roofing and Siding has the top rating (5.0★), and WMGB Home Improvement (Formerly West Michigan Glass Block) has the most reviews (1,477). Updated November 6, 2026.
10 companies that meet our bar: rated 4.5★ or higher on Google, with a meaningful review history (3,923 reviews combined) and currently operating. Request a call back and the company will phone you directly.
“I am extremely pleased with the preparatory work, the installation, and the follow-up. The staff members through the entire process were professional, attentive and there when they promised to be there. I…” — Google review
“They did a great job! I was grateful that they were transparent with the quote, they wanted me to pick them but weren't too "salesman" if that makes sense. Austin broke it down and gave me best case and worst case.…” — Google review
“We had our roof replaced by Roof Dr. and the process from them was very personal and seemless. Matt and Dan were both at my home doing inspections, their team did great work, worked hard and had the whole job…” — Google review
“My project installation went so well. Mitchell s was so polite, and helpful through the entire process. I am so pleased with everything!” — Google review
“Great company. Worked with Andrew of whom was great. Very professional and made sure all of our concerns were addressed. Would highly recommend.” — Google review
“Kaola Insulation is the best. Professional, knowledgeable and reasonably priced. They are customer centered and keep their word. Would definately recommend and would use them again.” — Google review
“This company customer service & services are beyond outstanding! Reasonable prices & friendly staff, will most definitely be recommending this company to family & friends.” — Google review
“I live in Coopersville Michigan and was in need of a new roof. Granville roofing and siding came highly recommended so I called and spoke with Aaron. From that first phone call to the very last visit on site Aaron…” — Google review
“10 STARS! Exceptional Service... Quality, Speed, & Price, it's not very often you get all 3. The team at Georgetown will take care of you like family. Absolutely the guys you want to call to get it done RIGHT!!” — Google review
“Great experience with Michigan Spray Foam Insulation. The team was professional and did an excellent job with my attic insulation. Highly recommend!” — Google review
We scan Google Maps for insulation contractor listings in and around Grandville, keep only open businesses whose main category matches the service, and require a Google rating of at least 4.5 from at least 20 reviews. Companies are ordered by a confidence-weighted score that balances rating and review volume. We do not accept payment for placement.
Grandville Roofing and Siding has the highest Google rating on our Grandville list: 5.0 out of 5 from 22 reviews (as of November 6, 2026).
WMGB Home Improvement (Formerly West Michigan Glass Block) has the most Google reviews among the companies listed here: 1,477, with a 4.9★ average.
Only open Grandville-area businesses whose Google category matches the service, rated at least 4.5★ from at least 20 Google reviews. They are ordered by a confidence-weighted score of rating and review volume. Placement is never paid.
Also in Grandville: Tire Shops
Analyzing 9,108,2729.1M ReviewsFor 25,80125.8K Experts